When and how would we adopt the euro?

We wouldn't get the euro automatically on day one after an accession agreement is ratified. Euro adoption runs through a well-tested three-step process, designed to protect both household finances and the stability of the economy along the way.

1. The waiting room: the króna under ECB protection

Shortly after joining, we would enter the European Exchange Rate Mechanism (ERM II), often called the "waiting room" for the euro. A fair central rate for the króna against the euro is set jointly by us, the European Central Bank (ECB), and the other member states — a rate that has to work for wage earners and exporters alike. The króna is then pegged to that rate within defined fluctuation bands.

We wouldn't be alone in the waiting room. Under ERM II, the ECB commits to defend the peg. If the króna comes under unusual pressure, the ECB is obliged to intervene — buying krónur with euros from its effectively bottomless reserves if needed. This isn't just theory:

• Denmark — which has a permanent peg to the euro — received a swap line from the ECB during the 2008 financial crisis, and again during the Covid crisis in 2020, most recently up to €24 billion, to ensure the Danish krone could weather the pressure.
• Croatia and Bulgaria came under currency market pressure in spring 2020, just before joining ERM II. The ECB responded by opening swap and repo lines, sending a clear signal to the market: the peg is defended. The pressure subsided immediately. Both countries have now gone all the way — Croatia adopted the euro in 2023, and Bulgaria at the most recent turn of the year.

2. The criteria: the Maastricht certificate

We need to stay in ERM II for at least two years. During that time, the economy has to demonstrate stability by meeting the so-called Maastricht criteria:

• Inflation cannot exceed by more than 1.5 percentage points the average of the three EU countries with the lowest inflation.
• Public finances: The government deficit cannot exceed 3% of GDP, and general government debt cannot exceed 60% of GDP.
• Long-term interest rates cannot exceed by more than 2 percentage points the rates in the three countries with the lowest inflation.
• Exchange rate stability: The króna must remain stable within ERM II for two years, without devaluation.

Our current position relative to the criteria is mixed.

• On the public-finance criteria we're close. General government debt on the Maastricht basis has, according to the OECD, fallen "from around 70% of GDP in 2020 to around 60% in 2024" after the HFF mortgage fund was wound down and part of Íslandsbanki was sold, and the deficit is within range.

• Interest rates and inflation, on the other hand, are more often than not too high here, as we all know firsthand. But that is precisely the point of ERM II: to change market expectations about the Icelandic króna, and with them the interest rates and inflation we actually live with.

Once a credible commitment is in place that krónur will convert to euros on a specific date, the market stops pricing Icelandic króna risk into interest rates; it starts pricing euros. The risk premium collapses — and lower rates then dampen inflation through the lending and housing markets, which in turn makes the inflation criterion easier to meet. A self-fulfilling prophecy, yes — but one resting on solid foundations.

These dynamics aren't theoretical. They are well documented in European financial history as a convergence play:

• Italy (1995–1998): Once the conviction that Italy would adopt the euro took hold, the risk premium on Italian government bonds fell from several hundred basis points over German bunds to around 25 basis points in just over three years — long before the euro itself arrived. Italy saved substantial sums in interest costs.
• Croatia (2020–2023): The risk premium on Croatian government bonds narrowed steadily from ERM II entry through to euro adoption, despite both the Covid crisis and the war in Ukraine during that period.
• Spain (1995–1999): The Spanish peseta had been devalued more than once inside ERM in the preceding years, and Spanish government bonds carried a thick risk premium. Once the belief that Spain would make it into the euro took hold, the premium fell from several hundred basis points to just a handful against German bunds — and Spain joined the euro in the first wave, in 1999.

The waiting room is therefore not just a waiting period, but the time when market expectations start working with us rather than against us.

3. The big day: automatic conversion

Once the criteria are met, the final, irrevocable conversion rate between króna and euro is locked in. Overnight — at a year-end, say — the switch happens:

• Automatic conversion: All amounts on bank accounts, payslips, mortgages, and in the pension funds' portfolios convert automatically into euros. You don't have to do anything.
• Values are preserved: This is a purely arithmetic conversion. No value is lost, either on assets or on debts. It's like switching from measuring your height in inches to using centimetres.
• The notes arrive: For the first few weeks you can still pay in shops with Icelandic krónur, but change always comes back in euros. The ECB and the Central Bank of Iceland handle getting new euro notes and coins out into the economy.

Euro adoption is therefore not a leap into the unknown, but a planned two- to three-year process with the European Central Bank as a backstop the whole way. When the day comes, we don't need to do anything — except perhaps get used to new notes in the wallet, and lower interest bills in the household budget.

Sources and further reading:

• European Commission: ERM II — the EU's Exchange Rate Mechanism — overview of how the mechanism works and how ECB intervention defends the currency within the fluctuation bands.
• European Central Bank: What does a country need to do to join the euro area? — explainer on the convergence (Maastricht) criteria covering inflation, debt, deficit, and interest rates.
• European Commission: Scenarios for adopting the euro — the official overview of the changeover process: locking in the conversion rate, the automatic electronic switch, and the cash exchange.
• Albrizio, Kataryniuk, Molina & Schäfer (2021): ECB Euro Liquidity Lines — academic analysis (Banco de España WP 2125, later published as IMF WP 2023/96) of how the ECB defended the currencies of Denmark, Croatia, Bulgaria and other non-euro-area countries through swap and liquidity lines.
• Treaty on the Functioning of the EU (TFEU), Article 140 — the legal basis for the Commission's assessment of whether a member state meets the conditions for euro adoption.
• OECD: Economic Surveys: Iceland 2025 — OECD review of the Icelandic economy, June 2025. Reports that general government gross debt on national accounts rules (ESA 2010, the same basis as the Maastricht criterion) fell from around 70% of GDP in 2020 to around 60% in 2024.